A. Biotite-granite. Liparose. Contains quartz, orthoclase, plagioclase (microperthite), biotite, magnetite, sphene, apatite, and zircon. P. R. C. 1340.

B. Basic segregation in biotite-granite. Akerose. Contains biotite, hornblende, quartz, plagioclase, microperthite, much sphene and apatite, some magnetite and zircon. P. R. C. 1338.

C. Another sample of B, but containing more hornblende. Akerose. P. R. C. 1339.

D. Nordmarkite.

Phlegrose. Contains orthoclase, plagioclase, quartz, hornblende, magnetite, apatite, and zircon, with very little biotite, titanite, diopside, and allanite. P. R. C. 1341.

E. Basic segregation in nordmarkite. Akerose. Contains hornblende, augite, microperthite, orthoclase, plagioclase, quartz, magnetite, zircon, and apatite. P. R. C. 1342.

F. Hornblende-paisanite. Liparose. Dike. Contains orthoclase, quartz, hornblende, magnetite, apatite, and zircon. P. R. C. 1347.

G. Nordmarkite. Phlegrose. Contains orthoclase, plagioclase, microperthite, hornblende, quartz, augite, magnetite, biotite, apatite, and zircon. P. R. C. 1343.

H. Hornblende-paisanite. Liparose. Composition like D, but with more quartz. P. R. C. 1348.

I. Basic segregation in H. Akerose. Contains hornblende, green and brown augite, biotite, quartz, microperthite, magnetite, little apatite, and zircon. P. R. C. 1349.

J. Diorite. Andose. Contains hornblende, augite, biotite, plagioclase, titaniferous magnetite, sphene, zircon, and quartz. P. R. C. 1344. K. Windsorite. Toscanose. Contains plagioclase, orthoclase, quartz, biotite, magnetite, ilmenite, and very small amounts of diopside, apatite, and zircon. P. R. C. 1345.

L. Basic segregation in diorite. Contains hornblende, augite, biotite, plagioclase, magnetite, apatite, zircon, and a little quartz. P. R. C. 1346.

M. Diabase. Camptonose. Contains plagioclase, augite, and mag

N. Camptonite. Camptonose. Contains brown hornblende, plagioclase, a little augite, olivine, magnetite, and apatite. P. R. C. 1350. O. Phyllite. Contains quartz, sericite, graphite?, magnetite, pyrite, rare orthoclase, plagioclase, sphene, and rutile. A quartz-sericite schist. P. R. C. 1352.

P. Cordierite-microperthite-hornfels. Akerose. Contains biotite, quartz, red garnet, corundum, magnetite, iolite, microperthite, and rarely pleonaste.

Q. Cordierite-hornfels. Contains quartz, biotite, pleonaste, corundum, iolite, magnetite, plagioclase, red garnet, and epidote?.

In these rocks the sulphur is all reckoned as pyrite, although pyrrhotite also is probably present. The carbonic acid represents either dolomite or siderite; not calcite. Traces of lithia and strontia occur in nearly all. Samples H, L, O, and Q contain traces of copper. In N there is 0.03 V2O,, a supplementary determination by Hillebrand.

A. Amphibolite, Guilford. Described by Emerson in Mon. XXIX. Contains hornblende needles, with albite and rutile. Analysis by L. G. Eakins, record No. 1326.

B. Granitoid gneiss, north of Lincoln's.

C. The same, west slope of Little Peco.

D. Chloritic granite. Yellowstonose. East Clarendon section.

E. Hornblende-granite. Hessose. East Clarendon.

Rocks B, C, D, and E collected by C. L. Whittle, but not described. Analyses by H. N. Stokes, record No. 1396.

A. Peridotite, Belchertown. Belcherose. Described by B. K. Emerson in Mon. XXIX. Contains hornblende, pyroxene, biotite, olivine, and magnetite. Analysis by L. G. Eakins, record No. 1326. B. Wehrlite, New Braintree. Cookose. Description furnished by Emerson. Contains diallage, enstatite, augite, anorthite, biotite, apatite, chromite, magnetite, and pyrrhotite. Analysis by L. G. Eakins, record No. 1327.

C. Black, serpentinized boltonite, Stow. Collected by Emerson. Analysis by W. F. Hillebrand, record No. 1555.